Minerals like quartz that break into pieces with jagged edges have conchoidal fracture.

Here's why:

* Conchoidal fracture is a type of fracture that produces curved, shell-like surfaces, often with sharp edges.

* This type of fracture is common in minerals with strong bonds and a lack of cleavage planes, like quartz.

* Cleavage refers to the tendency of a mineral to break along specific planes of weakness, resulting in flat, smooth surfaces.

So, while some minerals like mica have excellent cleavage, quartz lacks this characteristic. Instead, it breaks in a conchoidal manner, creating those jagged, sharp edges.